Method and means for producing blanks

ABSTRACT

This apparatus for cutting blanks intended for the manufacture of frustoconical containers is characterized in that it comprises a first pair of rotary cutting rollers provided with knife blades adapted to form in said strip a first transverse central arcuate cut line corresponding to the minor base of the developed frustoconical surface of said containers, together with a pair of small lateral radial cut lines intersecting the edges of the strip but leaving two small uncut portions in the strip between said small radial cut lines and said first central arcuate cut line, and another pair of rotary cutting rollers provided with a knife blade adapted to form in said strip another transverse central arcuate cut line corresponding to the major base of said developed frustoconical surface, said other arcuate cut line extending from one edge to the other edge of the strip and through said previously uncut portions, in order to sever a complete blank from the strip.

United States Patent [72] Inventor Louis Jean Chambon Paris, France [211 App]. No. 22,340 [22] Filed Mar. 24, 1970 [45] Patented Dec. 28, 1971 [73] Assignee Societe dEtudes de Machines Speciales Paris, France [32] Priority Mar. 28, 1969 [33] France [3 l 69 09455 [54] METHOD AND MEANS FOR PRODUCING BLANKS 5 Claims, 3 Drawing Figs.

[52] US. Cl 93/36 M, 83/49, 83/94, 83/300, 83/303, 93/58.4 [51] Int. Cl B26d 1/56 [50] Field of Search 83/49, 39, 103, 300-304, 926 R, 94; 93/58.4, 58.2, 39.3, 36.1, 36.2, 36 M [56] References Cited FOREIGN PATENTS 482,078 3/l938 Great Britain 93/58.4

Primary ExaminerJames M. Meister Attorneys- Robert E. Burns and Emmanuel .l. Lobato ABSTRACT: This apparatus for cutting blanks intended for the manufacture of frustoconical containers is characterized in that it comprises a first pair of rotary cutting rollers provided with knife blades adapted to form in said strip a first transverse central arcuate cut line corresponding to the minor base of the developed frustoconical surface of said containers, together with a pair of small lateral radial cut lines intersecting the edges of the strip but leaving two small uncut portions in the strip between said small radial outlines and said first central arcuate cut line, and another pair of rotary cutting rollers provided with a knife blade adapted to form in said strip another transverse central arcuate cut line corresponding to the major base of said developed frustoconical surface, said other arcuate cut line extending from one edge to the other edge of the strip and through said previously uncut portions. in order to sever a complete blank from the strip.

METHOD AND MEANS FOR PRODUCING BLANKS BACKGROUND OF THE INVENTION The present invention relate in general to methods and apparatus for producing blanks intended for the manufacture of frustoconical containers such as yaourt pots and the like, and has particular reference to improvements in these methods and apparatus.

As a rule, frustoconical pots and like containers are manufactured from cardboard strip stock cut into blanks having substantially the shape of annular sectors corresponding to the development of their frustoconical surface.

One of the methods now used in this field for producing these blanks consists roughly in a flat cutting operation performed by means of a thread or the like. In this method the blanks are trimmed after the cutting step in order to remove the wastes or scraps produced during this step. This flat cutting operation may be carried out either by using previously cut and printed sheets, or from a spool, by pulling the strip material therefrom and operating on a loop.

This flat cutting method is objectionable in that it is relatively inaccurate and slow. On the other hand, it requires relatively complicated manual operations.

Another blank cutting method known in the art is the socalled vertical cutting method wherein a sheet is cut by means of a punch-and-die unit operating on a loop portion of the sheet. This method is advantageous in comparison with the preceding one in that it eliminates the tedious manual trimming step, for the lace" consisting of the scraps resulting from the previous cutting operation is discharged on one side while the cut blanks are stacked vertically in a receiving SUMMARY OF THE INVENTION To this end, the method according to this invention of producing blanks intended for the manufacture of frustoconical containers, which blanks are cut from strip stock fed continuously and have each substantially the shape of an annular sector corresponding to the development of a frustoconical surface, is characterized in that there is formed firstly in said strip, during a single and same operation, a first transverse arcuate cut line corresponding to the minor base of the developed frustoconical surface and two radial cut lines corresponding to the side or end edges'of the blank, while leaving two small uncut portions between the first arcuate cut line and the pair of radial cut lines, whereafter a second transverse arcuate cut line is formed in the strip which corresponds to the major base of the developed frustoconical surface, said second cut line of a same blank being so positioned as to cut the strip material through the previously uncut portions left between the adjacent end portions of the first arcuate cut line and the pair of radial cut lines of the preceding blank, thus definitely severing said blank from the strip.

This invention is also concerned with an apparatus for the production of punched blanks for use in the manufacture of frustoconical containers, said blanks being cut by punching from strip stock fed continuously to form annular sectors corresponding in shape to the development of a frustoconical surface, this apparatus being characterized in that it comprises a first pair of rotary cutting rollers provided with knife blades adapted to form in said strip on the one hand a first transverse central arcuate cut line corresponding to the minor base of said developed frustoconical surface, and on the other hand a pair of lateral radial cut lines extending through the side edges of the strip and separated from said first transverse central arcuate out line by small uncut portions, and another pair of rotary cutting rollers also provided with knife blades adapted to form in said strip another transverse central arcuate out line corresponding to the major base of said developed frustoconical surface, said other arcuate cut line extending between the two edges of the strip and passing through said previously uncut portions in order to severe a blank from the strip.

According to a complementary feature characterizing this invention the lower roller of the second pair of rotary cutting rollers carries studs positioned to register with the scraps resulting from the cutting of said out lines, said studs being adapted to carry along the scraps towards an inclined plate for detaching the scraps from the studded roller and directing same to disposal means.

The method and apparatus of this invention are advantageous in that they afford a substantial increment in the production rate, which may be as highas 900 to 1,000 blanks per minute. Besides, any 'scraps resulting from the cutting operation are removed very easily. Finally, the blanks thus obtained may easily be picked up by a receiving device of the clamp or like type and stacked vertically so as to be ready for a subsequent packaging or other operation.

BRIEF DESCRIPTION OF THE DRAWING An exemplary form of embodiment of this invention will now be described with reference to the accompanying drawing in which:

FIG. I is a diagrammatic plan view from above showing an apparatus for producing blanks intended for manufacturing frustoconical containers, the rotary cutting rollers being removed from the apparatus to afford a clearer understanding of its operation;

FIG. 2 is a diagrammatic elevational view of the same apparatus;

FIG. 3 is a plan view showing on a larger scale one fraction of the strip, to illustrate the relative arrangement of the cut lines formed in the strip.

DESCRIPTION OF THE PREFERRED EMBODIMENT The blanks to be cut according to the method of this invention are obtained from strip stock 1 fed continuously from the right-hand end of FIGS. 1 and 2. This strip material may consist of thick paper, cardboard, metal sheet, plastics, etc. The strip 1 is fed firstly between a pair of lateral rotary trimming cutters 2 rotatably driven about horizontal axes in order to give a precise and constant width to the blank by removing a narrow marginal portion 3, 4 from each edge of the strip 1.

The strip 1 thus reduced to exactly the desired width is then fed between a first pair of rotary cutting rollers 5, 6 revolving about horizontal axes. The upper roller 4 carries three suitably shaped knife blades and the lower roller 6 acts as a counterpart. The knife blades are so disposed that, during each cutting operation, they form in the strip cut lines 7, 8 and 9, such as illustrated in FIG. 1.

The out line 7 extending transversely to the strip 1 is disposed centrally of this strip and has an arcuate shape corresponding to the minor base of the developed frustoconical surface corresponding to the final blank. The other two cut lines 8 and 9 extend substantially radially in relation to the transverse central arcuate cut line 7 and their outer portions intersect the edges Ia, lb of strip 1. On the other hand, these radial cut lines 8 and 9 are not connected to the central arcuate cut line 7, whereby small uncut portions 11, 12 are left in the strip 1 between the ends of the central arcuate cut line 7 and the inner ends of the radial cut lines 8 and 9.

The strip 1 thus cut is then fed to the left towards another pair of rotary cutting rollers l3, 14 having horizontal axes. The upper roller 13 carries a knife blade and the lower roller 14 acts as a counterpart. The knife blade of roller 13 is adapted to cut in the strip 1 a transverse arcuate out line 15 extending between the two edges la and lb of strip 1, this cut line corresponding to the major base of the developed frustoconical surface. The knife blade carried by roller 13 is so disposed that the cut line 15 corresponding to one blank is formed also through the small uncut portions 11 and 12 of the preceding blank.

Thus, the preceding blank is detached completely since a continuous out line is formed between the radial cut lines 8, 9 and the central cut line 7.

As clearly shown in FIG. 3, the cut line 15 intersects slightly the previously formed cut lines 7 and 9 approximately at a distance a of about 0.02 inches from the end of said cut lines 7, 9, to perit a clean separation of the blank.

Thus, on the outlet side of the pair of rotary cutting rollers 13 and 14 there are obtained blanks 16 having the shape of annular sectors corresponding to the developed shape of the frustoconical surface of the container to be manufactured therefrom. These blanks are subsequently carried along by small rollers 17 towards a clampor pinch-type receiving device 18 and directed thereby to an inclined plane device 19 where they are stacked vertically or substantially vertically.

As a consequence of the cutting operation performed by the second pair of rollers 13, 14, scraps 21, 22 and 23 are detached from the strip 1. The crescent-shaped central scrap 21 is bounded by the cut line 15 of one blank and by the cut line 7 of the preceding blank. The lateral scrap 22 is bounded by the cut line 15 of one blank, the radial cut line 9 of the preceding blank and the edge la of the strip, the other lateral scrap 23 being bounded by the cut line 15 of one blank, the radial cut line 8 of the preceding blank and the edge lb of the strip.

To facilitate the removal and disposal of these scraps, the lower roller 14 carries, at locations registering with these scraps, a plurality. of studs 24 adapted to penetrate the scraps and drive them towards an underlying comb-shaped plate 25. This plate 25 separates the scraps from the studs 24 and direct them to suitable disposal means.

While the invention has been described with reference to a single embodiment, it is not intended that is be limited thereby except insofar as appears in the accompanying claims.

lclaim:

1. A method of producing blanks intended for manufacturing frustoconical containers, said blanks being cut from strip stock fed continuously, each blank having the shape of an annular sector corresponding to the development of a frustoconical surface, characterized in that there is formed firstly in said strip, during a same and single operation, a first transverse arcuate cut line corresponding to the minor base of the developed frustoconical surface and two radial cut lines corresponding to the end edges of the blank, while leaving two small uncut portions between said first arcuate cut line and the pair of radial cut lines, whereafter'a second transverse arcuate cut line is formed in the strip which corresponds to the major base of the developed frustoconical surface, said second cut line of a same blank being so positioned as to cut the strip material through the previously uncut portions left between the adjacent end portions of the first arcuate cut line and the pair of radial cut lines of the preceding blank, thus definitely severing said blank from the strip.

2. An apparatus for manufacturing blanks intended for making frustoconical containers, said blanks being cut from a continuously-fed strip in the form of annular sectors cor-- responding to the development of a frustoconical surface, characterized in that it comprises a first pair of rotary cutting rollers provided with knife blades adapted to form in said strip on the one hand a first transverse central arcuate cut line corresponding to the minor base of said developed frustoconical surface, and on the other hand a pair of lateral radial cut lines extending through the side edges of the strip and separated from said first transverse central arcuate cut line by small uncut portions, and another pair of rotary cutting rollers also provided with knife blades adapted to form in said strip another transverse central arcuate cut line corresponding to the ma or base of said developed frustoconical surface, said other arcuate out line extending between the two edges of the strip and passing through said previously uncut portions in order to severe a blank from the strip.

3. An apparatus according to claim 2, characterized in that the lower roller of the second pair of cutting rollers carries studs so disposed as to register with the scraps resulting from the cutting of said cut lines, said studs being adapted to drive said scraps towards an underlying inclined plate for separating said scraps from said roller and direct them towards disposal means.

4. A method according to claim 1, characterized in that the blanks cut from said strip are transferred by a clamp-type receiving device to an inclined plane on which they are sub sequently stacked in a substantially vertical position.

5. Apparatus according to claim 2, further comprising an inclined plane and a clamp-type receiving means for transferring blanks cut from said strip to said inclined plane on which said blanks are stacked in a substantially vertical position. 

1. A method of producing blanks intended for manufacturing frustoconical containers, said blanks being cut from strip stock fed continuously, each blank having the shape of an annular sector corresponding to the development of a frustoconical surface, characterized in that there is formed firstly in said strip, during a same and single operation, a first transverse arcuate cut line corresponding to the minor base of the developed frustoconical surface and two radial cut lines corresponding to the end edges of the blank, while leaving two small uncut portions between said first arcuate cut line and the pair of radial cut lines, whereafter a second transverse arcuate cut line is formed in the strip which corresponds to the major base of the developed frustoconical surface, said second cut line of a same blank being so positioned as to cut the strip material through the previously uncut portions left between the adjacent end portions of the first arcuate cut line and the pair of radial cut lines of the preceding blank, thus definitely severing said blank from the strip.
 2. An apparatus for manufacturing blanks intended for making frustoconical containers, said blanks being cut from a continuously-fed strip in the form of annular sectors corresponding to the development of a frustoconical surface, characterized in that it comprises a first pair of rotary cutting rollers provided with knife blades adapted to form in said strip on the one hand a first transverse central arcuate cut line corresponding to the minor base of said developed frustoconical surface, and on the other hand a pair of lateral radial cut lines extending through the side edges of the strip and separated from said first transverse central arcuate cut line by small uncut portions, and another pair of rotary cutting rollers also provided with knife blades adapted to form in said strip another transverse central arcuate cut line corresponding to the major base of said developed frustoconical surface, said other arcuate cut line extending between the two edges of the strip and passing through said previously uncut portions in order to severe a blank from the strip.
 3. An apparatus according to claim 2, characterized in that the lower roller of the second pair of cutting rollers carries studs so disposed as to register with the scraps resulting from the cutting of said cut lines, said studs being adapted to drive said scraps towards an underlying inclined plate for separating said scraps from said roller and direct them towards disposal means.
 4. A method according to claim 1, characterized in that the blanks cut from said strip are transferred by a clamp-type receiving device to an inclined plane on which they are subsequently stacked in a substantially vertical position.
 5. Apparatus according to claim 2, further comprising an inclined plane and a clamp-type receiving means for transferring blanks cut from said strip to said inclined plane on which said blanks are stacked in a substantially vertical position. 